Semiconductor device manufacturing method and manufacturing system

Abstract

This method for manufacturing a semiconductor device includes a step a), a step b), a step c), and a step d). In step a), a sacrificial material is embedded in a recess formed in a substrate. In step b), the recess in which the sacrificial material is embedded is covered with a first sealing film. In step c), at least one of a process of heating the substrate and a process of irradiating the substrate with plasma is performed to decompose the sacrificial material in the recess, and the sacrificial material in the recess is removed through the first sealing film. In step d), a second sealing film is formed on the first sealing film.

Description

Semiconductor device manufacturing method and manufacturing system

[0001] Various aspects and embodiments of the present disclosure relate to methods and systems for manufacturing semiconductor devices.

[0002] For example, Patent Document 1 listed below discloses a method for manufacturing a semiconductor device, which includes: a first lamination step of laminating a thermally decomposable organic material on a substrate having a recess formed therein; a second lamination step of laminating a silicon nitride film on the organic material; and a desorption step of heating the substrate to a predetermined temperature to thermally decompose the organic material and desorbing the organic material below the silicon nitride film through the silicon nitride film, thereby forming an air gap between the silicon nitride film and the recess; and in the second lamination step, the silicon nitride film is laminated using microwave plasma while the temperature of the substrate is maintained at 200° C. or less.

[0003] Japanese Patent Application Laid-Open No. 2021-108353

[0004] The present disclosure provides a method and system for manufacturing a semiconductor device that can maintain the shape of an air gap even when another film is formed on the air gap.

[0005] One aspect of the present disclosure is a method for manufacturing a semiconductor device, including steps a), b), c), and d). In step a), a sacrificial material is embedded in a recess formed in a substrate. In step b), the recess with the sacrificial material embedded is covered with a first sealing film. In step c), the sacrificial material in the recess is decomposed by at least one of heating the substrate and irradiating the substrate with plasma, and the sacrificial material in the recess is removed via the first sealing film. In step d), a second sealing film is formed on the first sealing film.

[0006] According to various aspects and embodiments of the present disclosure, the shape of the air gap can be maintained even when another film is formed on the air gap.

[0007] FIG. 1 is a system configuration diagram illustrating an example of a manufacturing system according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of a film forming apparatus. FIG. 3 is a diagram illustrating an example of a plasma processing apparatus. FIG. 4 is a diagram illustrating an example of a heating apparatus. FIG. 5 is a flowchart illustrating an example of a method for manufacturing a semiconductor device. FIG. 6 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 7 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 8 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 9 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 10 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 11 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 12 is a diagram illustrating an example of a manufacturing process of a semiconductor device. FIG. 13 is a diagram illustrating an example of a relationship between the thickness of a first sealing film and the state of an air gap after removing a sacrificial material. FIG. 14 is a diagram illustrating an example of a relationship between the thickness of a second sealing film and the state of an air gap when another film is formed on the second sealing film.

[0008] Hereinafter, embodiments of the disclosed semiconductor device manufacturing method and manufacturing system will be described in detail with reference to the drawings. Note that the disclosed semiconductor device manufacturing method and manufacturing system are not limited to the following embodiments.

[0009] In the technology of Patent Document 1, if another film is formed on the sealing film after the air gap is formed, the material of the other film may penetrate into the air gap through the sealing film, resulting in the formation of the other film in the air gap. If the other film is formed in the air gap, the volume of the air gap becomes smaller than the desired volume. Furthermore, if the volume of the other film formed in the air gap differs between air gaps, volume variations occur among multiple air gaps. Therefore, it is desirable to suppress the formation of the other film in the air gap.

[0010] Therefore, the present disclosure provides a technique that can maintain the shape of the air gap even when another film is formed on the air gap.

[0011] [Configuration Example of Manufacturing System 10] FIG. 1 is a system configuration diagram illustrating an example of a manufacturing system 10 according to an embodiment of the present disclosure. The manufacturing system 10 includes a VTM (Vacuum Transfer Module) 11, multiple LLMs (Load Lock Modules) 12, and an EFEM (Equipment Front End Module) 13. A film forming apparatus 20, plasma processing apparatuses 30-1, 30-2, 30-3, and a heating apparatus 40 are connected to the sidewall of the VTM 11 via a gate valve G. Hereinafter, the plasma processing apparatuses 30-1, 30-2, and 30-3 will be collectively referred to as plasma processing apparatus 30 without distinction. Note that in the example of FIG. 1, one film forming apparatus 20 and one heating apparatus 40 are connected to the VTM 11, and three plasma processing apparatuses 30 are connected, but the disclosed technology is not limited thereto. In another embodiment, at least one of the film forming apparatuses 20 and the heating apparatuses 40 may be connected to the VTM 11 in plural. In another embodiment, the number of plasma processing apparatuses 30 connected to the VTM 11 may be two or less, or may be four or more.

[0012] The film forming apparatus 20 fills a recess formed in a substrate with a sacrificial material. In this embodiment, the sacrificial material is a thermally decomposable organic material. The film forming apparatus 20 is an example of a first processing apparatus.

[0013] The plasma processing apparatus 30-1 generates plasma and irradiates the substrate with activated species contained in the generated plasma, thereby removing unnecessary sacrificial material formed on the substrate. The plasma processing apparatus 30-1 also forms a first sealing film on the recess in which the sacrificial material is buried. The plasma processing apparatus 30 is an example of a second processing apparatus.

[0014] The plasma processing apparatus 30-2 forms a second sealing film on the first sealing film after the sacrificial material is removed. The plasma processing apparatus 30-2 is an example of a fourth processing apparatus. The plasma processing apparatus 30-3 forms another film on the substrate W on which the second sealing film has been formed.

[0015] The heating device 40 heats the substrate, on which the sacrificial material is embedded in the recesses and the first sealing film is formed, to thermally decompose the sacrificial material and remove it through the first sealing film. The heating device 40 is an example of a third processing device.

[0016] A plurality of LLMs 12 are connected to the other side wall of the VTM 11 via gate valves G. In the example of Fig. 1, two LLMs 12 are connected to the VTM 11, but the number of LLMs 12 connected to the VTM 11 may be more than two, or may be one.

[0017] A transfer robot 110 is disposed within the VTM 11. The transfer robot 110 transfers substrates between the film forming apparatus 20, the plasma processing apparatus 30, the heating apparatus 40, and the LLM 12. The interior of the VTM 11 is maintained at a predetermined pressure atmosphere that is lower than atmospheric pressure.

[0018] One sidewall of each LLM 12 is connected to the VTM 11 via a gate valve G, and the other sidewall is connected to the EFEM 13 via a gate valve G. When a substrate is carried into the LLM 12 from the EFEM 13 via the gate valve G, the gate valve G is closed and the pressure inside the LLM 12 is reduced to approximately the same pressure as the pressure inside the VTM 11. Then, the gate valve G is opened and the substrate inside the LLM 12 is carried out into the VTM 11 by the transfer robot 110.

[0019] Furthermore, with the pressure in the LLM 12 at approximately the same pressure as the pressure in the VTM 11, the transfer robot 110 transfers a substrate from the VTM 11 into the LLM 12 via the gate valve G, and the gate valve G is closed. Then, the pressure in the LLM 12 is increased to approximately the same pressure as the pressure in the EFEM 13. Then, the gate valve G is opened, and the substrate in the LLM 12 is transferred into the EFEM 13.

[0020] A plurality of load ports 14 are provided on the side wall of the EFEM 13 opposite to the side wall on which the gate valve G is provided. A container such as a FOUP (Front Opening Unified Pod) capable of accommodating a plurality of substrates is connected to each load port 14. An aligner module or the like that changes the orientation of the substrates may be provided inside the EFEM 13.

[0021] The inside of the EFEM 13 is, for example, atmospheric pressure. A transfer robot 130 is provided inside the EFEM 13. The transfer robot 130 transfers substrates between the LLM 12 and a container connected to the load port 14. An FFU (Fan Filter Unit) or the like is provided above the EFEM 13, and dry air from which particles and the like have been removed is supplied into the EFEM 13 from above, forming a downflow inside the EFEM 13. Note that in this embodiment, the inside of the EFEM 13 is atmospheric pressure; however, in another embodiment, the pressure inside the EFEM 13 may be controlled to be positive pressure. This makes it possible to suppress the intrusion of particles and the like into the EFEM 13 from the outside.

[0022] The control device 15 includes a memory, a processor, and an input / output interface. The memory stores a control program, processing recipes, and other data. The processor reads and executes the control program from the memory, and controls each part of the manufacturing system 10 via the input / output interface based on the recipes and other data stored in the memory.

[0023] 2 is a diagram showing an example of the film formation apparatus 20. The film formation apparatus 20 includes a chamber 21, an exhaust mechanism 22, a gas supply unit 23, a shower head 25, and a stage 26. In this embodiment, the film formation apparatus 20 is, for example, a chemical vapor deposition (CVD) apparatus.

[0024] The exhaust mechanism 22 has a vacuum pump that exhausts gas from the chamber 21 and a pressure adjustment valve that adjusts the pressure inside the chamber 21. The inside of the chamber 21 is controlled by the exhaust mechanism 22 to a vacuum atmosphere of a predetermined pressure.

[0025] A gas supply unit 23 that supplies multiple types of raw material monomers is connected to the chamber 21 via a shower head 25. In this embodiment, the multiple types of raw material monomers are, for example, isocyanate and amine. Isocyanate is an example of a first monomer, and amine is an example of a second monomer. The gas supply unit 23 has a raw material supply source 230a, a raw material supply source 230b, a vaporizer 231a, and a vaporizer 231b. The raw material supply source 230a contains, for example, an isocyanate liquid. The raw material supply source 230b contains, for example, an amine liquid.

[0026] The vaporizer 231a vaporizes the isocyanate liquid supplied from the raw material supply source 230a. The isocyanate vapor vaporized by the vaporizer 231a is introduced into the shower head 25 via the pipe 24a. The vaporizer 231b vaporizes the amine liquid supplied from the raw material supply source 230b. The amine vapor vaporized by the vaporizer 231b is introduced into the shower head 25 via the pipe 24b.

[0027] The shower head 25 is provided, for example, in the upper part of the chamber 21, and has a number of outlets formed on the bottom surface thereof. The shower head 25 discharges the isocyanate vapor introduced via the pipe 24a and the amine vapor introduced via the pipe 24b into the chamber 21 in a shower-like manner from separate outlets.

[0028] A stage 26 is provided within the chamber 21. The stage 26 has a temperature control mechanism (not shown). A substrate W is placed on the stage 26 and is loaded into the chamber 21 through an opening 21a formed in the sidewall of the chamber 21. The opening 21a is opened and closed by a gate valve G. The stage 26 has a temperature control mechanism, which controls the temperature of the substrate W so that the temperature is suitable for vapor deposition polymerization of the raw material monomers supplied from the gas supply unit 23. The temperature suitable for vapor deposition polymerization can be determined depending on the type of raw material monomer. The temperature suitable for vapor deposition polymerization is, for example, within a range of 60°C to 100°C.

[0029] Using such a film forming apparatus 20, a vapor deposition polymerization reaction of two types of raw material monomers occurs on the surface of the substrate W, thereby forming a polymer organic film on the surface of the substrate W. When the two types of raw material monomers are isocyanate and amine, a polymer organic film having polyurea bonds is formed on the surface of the substrate W. The polymer organic film is an example of a sacrificial material.

[0030] [Configuration Example of Plasma Processing Apparatus 30] Fig. 3 is a diagram showing an example of the plasma processing apparatus 30. The plasma processing apparatus 30 has a chamber 31 formed of a conductive material. The chamber 31 is grounded. An exhaust mechanism 32 is connected to the chamber 31. The exhaust mechanism 32 has a pressure adjustment valve. The exhaust mechanism 32 exhausts gas from the chamber 31 and controls the pressure adjustment valve so that the pressure inside the chamber 31 is set to a predetermined value.

[0031] A stage 33 on which a substrate W is placed is provided within the chamber 31. The substrate W is loaded into the chamber 31 through an opening 31a formed in the sidewall of the chamber 31 and placed on the stage 33. The opening 31a is opened and closed by a gate valve G. A heater 33a for heating the substrate W is provided within the stage 33. The stage 33 is electrically connected to the bottom of the chamber 31 and functions as an anode electrode. A shower head 34 is provided above the stage 33 so as to face the upper surface of the stage 33. The shower head 34 is made of a conductive material and is supported on the upper part of the chamber 31 via an insulating member 34a. A power source 35 that supplies high-frequency power for generating plasma is connected to the shower head 34. The shower head 34 functions as a cathode electrode with respect to the stage 33.

[0032] The gas supply source 36 supplies a process gas. The flow rate controller 37 adjusts the flow rate of the process gas supplied from the gas supply source 36 and supplies it into the diffusion space 34b of the shower head 34. The process gas supplied into the diffusion space 34b diffuses within the diffusion space 34b and is supplied in a shower-like manner into the chamber 31 from a plurality of outlet ports 34c formed on the lower surface of the diffusion space 34b. In the example of FIG. 3, one gas supply source 36 and one flow rate controller 37 are shown, but in reality, a set of the gas supply source 36 and the flow rate controller 37 is provided for each type of gas used.

[0033] The process gas supplied into the chamber 31 via the shower head 34 is converted into plasma by high-frequency power supplied into the chamber 31 from the power source 35. Then, ions, active species, and the like contained in the plasma remove a portion of the sacrificial material formed on the substrate W, and a first sealing film, a second sealing film, and other films are formed on the substrate W. In this embodiment, the first sealing film, the second sealing film, and other films are, for example, silicon oxide films. As another example, the first sealing film and the second sealing film may be other silicon-containing films, such as silicon nitride films.

[0034] 4 is a diagram showing an example of the heating device 40. The heating device 40 has a chamber 41, an exhaust pipe 42, a supply pipe 43, a stage 44, a lamp house 45, and a lamp 46.

[0035] A stage 44 on which a substrate W is placed is provided within the chamber 41. A lamp house 45 is provided at a position opposite to the surface of the stage 44 on which the substrate W is placed. A lamp 46 such as an infrared lamp is disposed within the lamp house 45.

[0036] A gas supply unit 47 is connected to the sidewall of the chamber 41 via a supply pipe 43. The gas supply unit 47 supplies an inert gas such as N2 gas into the chamber 41 via the supply pipe 43. An opening 41a for loading and unloading a substrate W is also formed in the sidewall of the chamber 41. The opening 41a is opened and closed by a gate valve G.

[0037] An exhaust device 48 is connected to the bottom of the chamber 41 via an exhaust pipe 42. The exhaust device 48 has a pressure adjustment valve. The exhaust device 48 exhausts gas from the chamber 41 and controls the pressure adjustment valve so that the pressure inside the chamber 41 becomes a predetermined pressure.

[0038] With the substrate W placed on the stage 44 and inert gas being supplied into the chamber 41 via the supply pipe 43, the lamp 46 is turned on, thereby heating the substrate W to a predetermined temperature in the inert gas atmosphere. In this embodiment, the substrate W is heated to a temperature of, for example, 400° C. or less.

[0039] [Method of Manufacturing a Semiconductor Device] Fig. 5 is a flowchart showing an example of a method of manufacturing a semiconductor device. The manufacturing method illustrated in Fig. 5 is realized by the control device 15 controlling each part of the manufacturing system 10. An example of the method of manufacturing a semiconductor device will be described below with reference to Figs. 6 to 12.

[0040] First, the substrate W is loaded into the chamber 21 of the film forming apparatus 20 (step S100). In step S100, the substrate W having the recess 60 formed thereon is loaded into the chamber 21 of the film forming apparatus 20, for example, as shown in FIG.

[0041] Next, a sacrificial material is embedded in the recess 60 (step S101). Step S101 is an example of process a). In step S101, a first monomer and a second monomer are supplied into the chamber 21, and a vapor deposition polymerization reaction of the first monomer and the second monomer occurs, thereby embedding the sacrificial material in the recess 60 of the substrate W. In this embodiment, the first monomer is, for example, an isocyanate, the second monomer is, for example, an amine, and the sacrificial material has a polyurea bond. As a result, the sacrificial material 61 is embedded in the recess 60, as shown in FIG. 7 , for example.

[0042] In step S101, the sacrificial material 61 is embedded in the recess of the substrate W under the following processing conditions, for example: Pressure in the chamber 21: 0.5 to 20 Torr (66.7 to 2666 Pa) Flow rate of isocyanate vapor: 1 to 20 sccm (0.0017 to 0.034 Pa·m 3 / s) Flow rate of amine vapor: 1 to 20 sccm (0.0017 to 0.034 Pa m 3 / s) Temperature of substrate W: 40 to 150°C

[0043] Next, the substrate W is transferred from the film forming apparatus 20 to the plasma processing apparatus 30-1 (step S102). In step S102, the transfer robot 110 in the VTM 11 transfers the substrate W out of the chamber 21 of the film forming apparatus 20 and into the chamber 31 of the plasma processing apparatus 30-1.

[0044] Next, unnecessary sacrificial material 61 on the substrate W is removed (step S103). In step S103, plasma is generated from a processing gas in the chamber 31. The processing gas is, for example, a mixed gas of hydrogen gas and nitrogen gas. Then, the generated plasma removes the unnecessary sacrificial material 61 formed around the recess 60, for example, as shown in FIG. 8. In step S103, the unnecessary sacrificial material 61 is removed by the plasma processing apparatus 30 under, for example, the following processing conditions: Pressure in the chamber 31: 0.05 to 1.0 Torr (6.67 to 133 Pa) Processing gas: H2 / N2=100 to 300 sccm / 100 to 300 sccm (0.17 to 0.51 Pa·m 3 / s / 0.17 to 0.51 Pa·m 3 / s) High frequency power: 100 to 400 W Temperature of substrate W: 40 to 200°C

[0045] Next, a first sealing film is formed on the recess 60 in which the sacrificial material 61 is buried (step S104). Step S104 is an example of process b). In step S104, plasma is generated from a process gas such as organic aminosilane in the chamber 31. Then, the generated plasma forms a first sealing film 62 on the recess 60 in which the sacrificial material 61 is buried, as shown in FIG. 9 .

[0046] In this embodiment, the thickness of the first sealing film 62 is 1.6 nm or more and 2.4 nm or less. Furthermore, a plurality of openings are formed in the first sealing film 62, and the maximum diameter of the openings is 0.7 nm or more. In step S104, the first sealing film 62 is formed by the plasma processing apparatus 30 under the following processing conditions, for example: Pressure in the chamber 31: 0.1 to 10 Torr (13.3 to 1333 Pa) Processing gas: organic aminosilane = 10 to 50 sccm (0.017 to 0.085 Pa m 3 / s) High frequency power: 50 to 200 W Temperature of substrate W: 20 to 200°C

[0047] Next, the substrate W is transferred from the plasma processing apparatus 30-1 to the heating apparatus 40 (step S105). In step S105, the substrate W is transferred from the chamber 31 of the plasma processing apparatus 30 to the chamber 41 of the heating apparatus 40 by the transfer robot 110 in the VTM 11.

[0048] Next, the substrate W is heated (step S106). Step S106 is an example of process d). In step S106, the substrate W is heated to a temperature of, for example, 400° C. or less, whereby the sacrificial material 61 is thermally decomposed and released through the first sealing film 62.

[0049] Here, the size of the molecules of the first monomer and the second monomer is 0.7 nm or less, and when heated, the molecules of the first monomer and the second monomer are decomposed into even smaller molecules. Furthermore, the maximum diameter of the opening in the first sealing film 62 is 0.7 nm or more. Therefore, the molecules of the first monomer and the second monomer thermally decomposed from the sacrificial material 61 can be released from the recess 60 via the first sealing film 62. As a result, an air gap 63 is formed between the first sealing film 62 and the recess 60, as shown in FIG. 10 , for example.

[0050] In step S106, the substrate W is heated under the following processing conditions, for example: Pressure in the chamber 41: 0.5 to 20 Torr (66.7 to 2666 Pa) Gas supplied into the chamber 41: N2=200 to 2000 sccm (0.34 to 3.4 Pa·m 3 / s) Temperature of substrate W: 350 to 400°C

[0051] Next, the substrate W is transferred from the heating device 40 to the plasma processing device 30-2 (step S107). In step S107, the transfer robot 110 in the VTM 11 transfers the substrate W out of the chamber 41 of the heating device 40 and into the chamber 31 of the plasma processing device 30-2.

[0052] Next, a second sealing film is formed on the first sealing film (step S108). Step S108 is an example of process d). In step S108, plasma is generated from a process gas such as organic aminosilane in chamber 31. Then, the generated plasma forms a second sealing film 64 on the first sealing film 62, as shown in FIG. 11 .

[0053] In this embodiment, the thickness of the second sealing film 64 is 1.2 nm or more. In addition, the maximum diameter of the opening in the sealing film including the first sealing film 62 and the second sealing film 64 is 0.35 nm or less. In step S108, the second sealing film 64 is formed by the plasma processing device 30 under the following processing conditions, for example: Pressure in the chamber 31: 0.1 to 10 Torr (13.3 to 1333 Pa) Processing gas: organic aminosilane = 10 to 50 sccm (0.017 to 0.085 Pa m 3 / s) High frequency power: 50 to 200 W Temperature of substrate W: 20 to 110°C

[0054] Next, the substrate W is transferred from the plasma processing apparatus 30-2 to the plasma processing apparatus 30-3 (step S109). In step S109, the transfer robot 110 in the VTM 11 transfers the substrate W out of the chamber 31 of the plasma processing apparatus 30-2 and into the chamber 31 of the plasma processing apparatus 30-3.

[0055] Next, another film is formed on the second sealing film (step S110). In step S110, plasma is generated from a processing gas such as DIPAS (DiIsoPropylAminoSilane) in the chamber 31. The generated plasma then forms another film 65 on the second sealing film 64. In this embodiment, the other film 65 is, for example, a silicon oxide film.

[0056] In step S110, another film 65 is formed by the plasma processing apparatus 30 under the following processing conditions, for example: Pressure in the chamber 31: 0.1 to 10 Torr Processing gas: DIPAS=5 to 100 sccm High frequency power: 50 to 200 W Temperature of the substrate W: 20 to 200° C.

[0057] Next, the substrate W is unloaded from the plasma processing apparatus 30-3 (step S111), and the method for manufacturing a semiconductor device shown in this flowchart is completed.

[0058] Here, the size of the DIPAS molecules is 0.5 to 1.0 nm. Furthermore, in the sealing films including the first sealing film 62 and the second sealing film 64, the maximum diameter of the opening is 0.35 nm or less. Therefore, the first sealing film 62 and the second sealing film 64 can prevent the material of the other film 65 from penetrating into the recess 60. As a result, even after the other film 65 is formed on the second sealing film 64 in step S110, the shape of the air gap 63 can be maintained, as shown in FIG. 12, for example.

[0059] The other film 65 formed on the second sealing film 64 is preferably formed by CVD. This makes it easier for molecules contained in the source gas of the other film 65 to be adsorbed to the second sealing film 64 when passing through the openings in the second sealing film 64. Therefore, it is possible to reduce the number of molecules of the source gas that completely pass through the openings in the second sealing film 64 and reach the recess 60.

[0060] [Experimental Results] FIG. 13 is a diagram showing an example of the relationship between the thickness of the first sealing film 62 and the state of the air gap 63 after the sacrificial material 61 is removed.

[0061] When the thickness of the first sealing film 62 was 1.2 nm, heating the substrate W after the first sealing film 62 was formed broke the first sealing film 62, and no air gaps 63 were formed. When the thickness of the first sealing film 62 was 2.8 nm, heating the substrate W after the first sealing film 62 was formed did not sufficiently remove the sacrificial material 61 from the air gaps 63, and the sacrificial material 61 remained as residue in the air gaps 63.

[0062] On the other hand, when the thickness of the first sealing film 62 is 1.6 nm to 2.4 nm, when the substrate W is heated after the first sealing film 62 is formed, the sacrificial material 61 in the air gap 63 is sufficiently removed, and no residue is found in the air gap 63. Therefore, the thickness of the first sealing film 62 is preferably 1.6 nm to 2.4 nm.

[0063] 14 is a diagram showing an example of the relationship between the thickness of the second sealing film 64 and the state of the air gap 63 when another film 65 is formed on the second sealing film 64. In the example of FIG. 14, an experiment was conducted with the thickness of the first sealing film 62 being 2.0 nm.

[0064] When the thickness of the second sealing film 64 is 0.4 nm, when another film 65 is formed on the second sealing film 64, the inside of the recess 60 is also filled with the other film 65. This is thought to be because molecules contained in the material gas of the other film 65 penetrate into the recess 60 through the first sealing film 62 and the second sealing film 64.

[0065] On the other hand, when the thickness of the second sealing film 64 is 1.2 nm, even if another film 65 is formed on the second sealing film 64, the other film 65 is not formed in the recess 60. That is, when the thickness of the second sealing film 64 is 1.2 nm, the first sealing film 62 and the second sealing film 64 prevent molecules contained in the source gas of the other film 65 from penetrating into the recess 60. Therefore, it is preferable that the thickness of the second sealing film 64 is 1.2 nm or more.

[0066] The embodiment has been described above. As described above, the method for manufacturing a semiconductor device in this embodiment includes steps a), b), c), and d). In step a), a sacrificial material (sacrificial material 61) is embedded in a recess (recess 60) formed in a substrate (substrate W). In step b), the recess embedded with the sacrificial material is covered with a first sealing film (first sealing film 62). In step c), the substrate is heated to decompose the sacrificial material in the recess, and the sacrificial material in the recess is removed via the first sealing film. In step d), a second sealing film (second sealing film 64) is formed on the first sealing film. This allows the shape of the air gap to be maintained even if another film is formed on the air gap.

[0067] In the above embodiment, the thickness of the first sealing film is 1.6 nm or more and 2.4 nm or less, which allows an air gap with a desired volume to be formed.

[0068] In the above-described embodiment, the temperature of the substrate may be controlled to room temperature in step b), which makes it easier to control the temperature of the substrate in step b).

[0069] In the above-described embodiment, the thickness of the second sealing film is 1.2 nm or more, which allows an air gap with a desired volume to be formed.

[0070] In the above-described embodiment, the first sealing film and the second sealing film are silicon-containing films such as silicon oxide films or silicon nitride films, thereby forming an air gap with a desired volume.

[0071] In the above-described embodiment, the second sealing film is formed using DIPAS (DiIsoPropylAminoSilane) gas, which allows the shape of the air gap to be maintained even when another film is formed on the air gap.

[0072] The method for manufacturing a semiconductor device according to the above embodiment further includes step e), which is performed between steps b) and c), and includes removing at least a portion of the sacrificial material on the substrate by heating the substrate or irradiating the substrate with plasma, thereby forming an air gap of a desired volume.

[0073] In the above-described embodiment, the sacrificial material may be a thermally decomposable organic material. In step a), gases of a first monomer and a second monomer are supplied into a chamber into which the substrate is loaded, and the sacrificial material is embedded in the recess by vapor deposition polymerization of the first monomer and the second monomer, where the first monomer is an isocyanate, the second monomer is an amine, and the sacrificial material contains a urea bond. This allows an air gap of a desired volume to be formed.

[0074] The semiconductor device manufacturing system (manufacturing system 10) in the above-described embodiment includes a first processing apparatus (film formation apparatus 20), a second processing apparatus (plasma processing apparatus 30-1), a third processing apparatus (heating apparatus 40), a fourth processing apparatus (plasma processing apparatus 30-2), and a control apparatus (control apparatus 15) that controls the first processing apparatus, the second processing apparatus, the third processing apparatus, and the fourth processing apparatus. The control apparatus performs steps a), b), c), and d). In step a), a sacrificial material is embedded in the recess using the first processing apparatus. In step b), the recess into which the sacrificial material is embedded is covered with a first sealing film using the second processing apparatus. In step c), a substrate is heated using the third processing apparatus, thereby decomposing the sacrificial material in the recess and removing the sacrificial material in the recess via the first sealing film. In step d), a second sealing film is formed on the first sealing film using the fourth processing apparatus. This allows the shape of the air gap to be maintained even if another film is formed on the air gap.

[0075] [Others] The technology disclosed in the present application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.

[0076] For example, in the above-described embodiment, the sacrificial material 61 is removed by heating the substrate W in step S106, but the disclosed technology is not limited to this. For example, as another embodiment, the substrate W may be irradiated with plasma in step S106. As a result, active species, ions, etc. contained in the plasma are supplied to the sacrificial material 61 in the recess 60 through the first sealing film 62, and the sacrificial material 61 is decomposed and removed by the active species, ions, etc. contained in the plasma.

[0077] Furthermore, when the substrate W is irradiated with plasma in step S106, the substrate W may be further heated, thereby enabling the sacrificial material 61 in the recess 60 to be removed more quickly. Note that the plasma irradiated to the substrate W in step S106 is preferably generated using microwaves.

[0078] Furthermore, in the above-described embodiment, a thermally decomposable organic material is used as the sacrificial material 61, but the disclosed technology is not limited to this. For example, in other embodiments, a silicon-containing material such as amorphous silicon or a carbon-containing material such as amorphous carbon may be used as the sacrificial material 61. When such a material is used as the sacrificial material 61, the sacrificial material 61 is removed using plasma in step S106. Furthermore, when a silicon-containing material is used as the sacrificial material 61, a gas containing oxygen gas, for example, is used as the process gas used to generate the plasma. Furthermore, when a carbon-containing material is used as the sacrificial material 61, for example, oxygen gas is used as the process gas used to generate the plasma.

[0079] In the above embodiment, capacitively coupled plasma is used as the plasma source in steps S103, S104, and S108, but the disclosed technology is not limited to this. As an alternative, other plasma sources such as microwave plasma, inductively coupled plasma, and magnetron plasma may be used as the plasma source in steps S103, S104, and S108.

[0080] In the above-described embodiment, the thermally decomposable polymer sacrificial material 61 having a urea bond (—NH—CO—NH—) is formed on the surface of the substrate W using an isocyanate as the first monomer and an amine as the second monomer, but the disclosed technology is not limited to this. For example, the thermally decomposable polymer sacrificial material 61 having a 2-aminoethanol bond (—NH—CH2-CH(OH)—) may be formed on the surface of the substrate W using an epoxide as the first monomer and an amine as the second monomer. Alternatively, the thermally decomposable polymer sacrificial material 61 having a urethane bond (—NH—CO—O—) may be formed on the surface of the substrate W using an isocyanate as the first monomer and an alcohol as the second monomer. Alternatively, the thermally decomposable polymer sacrificial material 61 having an amide bond (—NH—CO—) may be formed on the surface of the substrate W using an acyl halide as the first monomer and an amine as the second monomer. Alternatively, a thermally decomposable polymeric sacrificial material 61 having imide bonds (—CO—N(−)—CO—) may be formed on the surface of the substrate W using a carboxylic acid anhydride as the first monomer and an amine as the second monomer.

[0081] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

[0082] Furthermore, the following supplementary notes are disclosed regarding the above-described embodiment.

[0083] (Supplementary Note 1) A method for manufacturing a semiconductor device, comprising: a) embedding a sacrificial material in a recess formed in a substrate; b) covering the recess in which the sacrificial material is embedded with a first sealing film; c) decomposing the sacrificial material in the recess by at least one of heating the substrate and irradiating the substrate with plasma, and removing the sacrificial material in the recess through the first sealing film; and d) forming a second sealing film on the first sealing film. (Supplementary Note 2) The method for manufacturing a semiconductor device according to Supplementary Note 1, wherein the first sealing film has a thickness of 1.6 nm or more and 2.4 nm or less. (Supplementary Note 3) The method for manufacturing a semiconductor device according to Supplementary Note 1 or 2, wherein in step b), the temperature of the substrate is controlled to room temperature. (Supplementary Note 4) The method for manufacturing a semiconductor device according to any one of Supplements 1 to 3, wherein the second sealing film has a thickness of 1.2 nm or more. (Supplementary Note 5) The method for manufacturing a semiconductor device according to any one of Supplementary Notes 1 to 4, wherein the first sealing film and the second sealing film are silicon-containing films. (Supplementary Note 6) The method for manufacturing a semiconductor device according to Supplementary Note 5, wherein the first sealing film and the second sealing film are silicon oxide films or silicon nitride films. (Supplementary Note 7) The method for manufacturing a semiconductor device according to Supplementary Note 6, wherein the second sealing film is formed using DIPAS (DiIsoPropylAminoSilane) gas. (Supplementary Note 8) The method for manufacturing a semiconductor device according to any one of Supplementary Notes 1 to 7, further comprising: e) a step performed between step b) and step c), wherein the step is to remove at least a portion of the sacrificial material on the substrate by performing at least one of a process of heating the substrate and a process of irradiating the substrate with plasma. (Appendix 9) The method for manufacturing a semiconductor device according to any one of Appendices 1 to 8, wherein the sacrificial material is a thermally decomposable organic material, and in the step a), gases of a first monomer and a second monomer are supplied into a chamber into which a substrate is carried, and the sacrificial material is embedded in the recess by vapor deposition polymerization of the first monomer and the second monomer, the first monomer is isocyanate, the second monomer is an amine, and the sacrificial material contains a urea bond.(Supplementary Note 10) A semiconductor device manufacturing system comprising: a first processing apparatus; a second processing apparatus; a third processing apparatus; a fourth processing apparatus; and a control apparatus that controls the first processing apparatus, the second processing apparatus, the third processing apparatus, and the fourth processing apparatus, wherein the control apparatus executes the following steps: a) using the first processing apparatus, embedding a sacrificial material in a recess formed in a substrate; b) using the second processing apparatus, covering the recess into which the sacrificial material is embedded with a first sealing film; c) using the third processing apparatus, performing at least one of a process of heating the substrate and a process of irradiating the substrate with plasma to decompose the sacrificial material in the recess and remove the sacrificial material in the recess via the first sealing film; and d) using the fourth processing apparatus, forming a second sealing film on the first sealing film.

[0084] G: Gate valve W: Substrate 10: Manufacturing system 11: VTM 110: Transfer robot 12: LLM 13: EFEM 130: Transfer robot 14: Load port 15: Control device 20: Film deposition device 30: Plasma treatment device 40: Heating device 60: Recess 61: Sacrificial material 62: First sealing film 63: Air gap 64: Second sealing film 65: Other film

Claims

1. a) A step of embedding a sacrificial material into a recess formed in a substrate; b) A step of covering the recess in which the sacrificial material is embedded with a first sealing film; c) By performing at least one of a process of heating the substrate and a process of irradiating the substrate with plasma, decomposing the sacrificial material in the recess and removing the sacrificial material in the recess through the first sealing film; d) A step of forming a second sealing film on the first sealing film. A method for manufacturing a semiconductor device including these steps.

2. The method for manufacturing a semiconductor device according to claim 1, wherein the thickness of the first sealing film is a thickness of 1.6 nm or more and 2.4 nm or less.

3. The method for manufacturing a semiconductor device according to claim 1, wherein in step b), the temperature of the substrate is controlled to room temperature.

4. The method for manufacturing a semiconductor device according to claim 1, wherein the thickness of the second sealing film is a thickness of 1.2 nm or more.

5. The method for manufacturing a semiconductor device according to claim 1, wherein the first sealing film and the second sealing film are silicon-containing films.

6. The method for manufacturing a semiconductor device according to claim 5, wherein the first sealing film and the second sealing film are a silicon oxide film or a silicon nitride film.

7. The method for manufacturing a semiconductor device according to claim 6, wherein the second sealing film is formed using a gas of DiIsoPropylAminoSilane (DIPAS).

8.

7. A method for manufacturing a semiconductor device according to claim 1, further including e) A step that is executed between step b) and step c), and by performing at least one of a process of heating the substrate and a process of irradiating the substrate with plasma, removing at least a part of the sacrificial material on the substrate.

9. The sacrificial material is a thermally decomposable organic material. In step a), a gas of a first monomer and a second monomer is supplied into a chamber into which the substrate is carried in, and the sacrificial material is embedded in the recess by vapor deposition polymerization of the first monomer and the second monomer. The first monomer is isocyanate, the second monomer is amine, and the sacrificial material contains a urea bond. The method for manufacturing a semiconductor device according to claim 1.

10. A semiconductor device manufacturing system comprising: a first processing device, a second processing device, a third processing device, a fourth processing device, and a control device for controlling the first processing device, the second processing device, the third processing device, and the fourth processing device, wherein the control device performs: a) a step of embedding a sacrificial material into a recess formed in a substrate using the first processing device; b) a step of covering the recess in which the sacrificial material is embedded with a first sealing film using the second processing device; c) a step of decomposing the sacrificial material in the recess and removing the sacrificial material in the recess through the first sealing film by performing at least one of a process of heating the substrate and a process of irradiating the substrate with plasma using the third processing device; and d) a step of forming a second sealing film on the first sealing film using the fourth processing device.

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